1. Field of the Invention
This invention relates to a means for moving the tray receiving a compact disk in a CD-ROM drive, and more particularly to moving this tray by means a mechanism otherwise used to read data from the compact disk.
2. Background Information
The CD-ROM (Compact Disk--Read Only Memory) drive is becoming increasingly important as a data input means for personal computers. While this type of drive, using optically-read compact disks, provides a read only function, without providing a corresponding capability to write information on the system, the compact disks have a significant advantage of much greater storage capacity, up to 600 megabytes of information, than conventional magnetic disks.
The methods of handling the insertion and removal of the magnetic disks and compact disks into their respective types of drives are quite different. Magnetic disks are typically held within cartridges are inserted into a slot within the drive, to be latched in place when fully inserted. Within the cartridges, the disks are allowed to rotate and to move as required for centering on a drive mechanism. For example, 3.5-inch magnetic disk cartridges are inserted between two raised plates, which are dropped when the disk is fully inserted to engage the drive mechanism. To eject these cartridges, an ejection mechanism raises the plates to again align with the slot and pushes the cartridge partly out through the slot. The ejection mechanism is operated either manually, through the use of a mechanical pushbutton on the front of the drive, or electronically, through the use of a DC motor driving a pin to release a mechanism. In the case of electronic ejection, the ejection action may be started through an operator action, such as pushing an electrical button somewhere on the system, typing an eject command, or selecting an appropriate icon on the display screen.
On the other hand, in a CD-ROM drive, the compact disk is typically handled on a disk handling tray, which is moved outward for the removal or installation of a disk, and returned inward so that information on the disk can be read. Normally, in computer applications, the compact disk is handled directly, without being enclosed in a cassette. The CD-ROM drive also includes a spindle motor, which rotates the disk when it is installed within the drive, and an actuator motor, which moves an optical arrangement in a radial direction relative to the disk to accomplish the sequential reading of information on the compact disk. The movement of the disk handling tray is typically provided through the use of an additional motor, avoiding a reliance on the dynamics provided by the system user to load or unload the drive. However, to reduce both the initial cost of the drive and the space required for its components, what is needed is a means providing for movement of the tray through the use of a mechanical drive required for the reading of data stored on the disk.